// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// TODO(awalker): clean up the const/non-const reference handling in this test

#include "skia/ext/platform_canvas.h"

#include <stdint.h>

#include "base/logging.h"
#include "build/build_config.h"
#include "skia/ext/platform_device.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkColor.h"
#include "third_party/skia/include/core/SkColorPriv.h"
#include "third_party/skia/include/core/SkPixelRef.h"

#if defined(OS_MACOSX)
#import <ApplicationServices/ApplicationServices.h>
#endif

#if !defined(OS_WIN)
#include <unistd.h>
#endif

namespace skia {

namespace {

#if defined(OS_WIN)
    void MakeOpaque(SkCanvas* canvas, int x, int y, int width, int height)
    {
        if (width <= 0 || height <= 0)
            return;

        SkRect rect;
        rect.setXYWH(SkIntToScalar(x), SkIntToScalar(y),
            SkIntToScalar(width), SkIntToScalar(height));
        SkPaint paint;
        paint.setColor(SK_ColorBLACK);
        paint.setXfermodeMode(SkXfermode::kDstATop_Mode);
        canvas->drawRect(rect, paint);
    }
#endif

    bool IsOfColor(const SkBitmap& bitmap, int x, int y, uint32_t color)
    {
        // For masking out the alpha values.
        static uint32_t alpha_mask = static_cast<uint32_t>(SK_A32_MASK) << SK_A32_SHIFT;
        return (*bitmap.getAddr32(x, y) | alpha_mask) == (color | alpha_mask);
    }

    // Return true if the canvas is filled to canvas_color, and contains a single
    // rectangle filled to rect_color. This function ignores the alpha channel,
    // since Windows will sometimes clear the alpha channel when drawing, and we
    // will fix that up later in cases it's necessary.
    bool VerifyRect(const SkCanvas& canvas,
        uint32_t canvas_color, uint32_t rect_color,
        int x, int y, int w, int h)
    {
        const SkBitmap bitmap = skia::ReadPixels(const_cast<SkCanvas*>(&canvas));
        SkAutoLockPixels lock(bitmap);

        for (int cur_y = 0; cur_y < bitmap.height(); cur_y++) {
            for (int cur_x = 0; cur_x < bitmap.width(); cur_x++) {
                if (cur_x >= x && cur_x < x + w && cur_y >= y && cur_y < y + h) {
                    // Inside the square should be rect_color
                    if (!IsOfColor(bitmap, cur_x, cur_y, rect_color))
                        return false;
                } else {
                    // Outside the square should be canvas_color
                    if (!IsOfColor(bitmap, cur_x, cur_y, canvas_color))
                        return false;
                }
            }
        }
        return true;
    }

#if !defined(USE_AURA) && !defined(OS_MACOSX)
    // Return true if canvas has something that passes for a rounded-corner
    // rectangle. Basically, we're just checking to make sure that the pixels in the
    // middle are of rect_color and pixels in the corners are of canvas_color.
    bool VerifyRoundedRect(const SkCanvas& canvas,
        uint32_t canvas_color,
        uint32_t rect_color,
        int x,
        int y,
        int w,
        int h)
    {
        SkBaseDevice* device = skia::GetTopDevice(canvas);
        const SkBitmap& bitmap = device->accessBitmap(false);
        SkAutoLockPixels lock(bitmap);

        // Check corner points first. They should be of canvas_color.
        if (!IsOfColor(bitmap, x, y, canvas_color))
            return false;
        if (!IsOfColor(bitmap, x + w, y, canvas_color))
            return false;
        if (!IsOfColor(bitmap, x, y + h, canvas_color))
            return false;
        if (!IsOfColor(bitmap, x + w, y, canvas_color))
            return false;

        // Check middle points. They should be of rect_color.
        if (!IsOfColor(bitmap, (x + w / 2), y, rect_color))
            return false;
        if (!IsOfColor(bitmap, x, (y + h / 2), rect_color))
            return false;
        if (!IsOfColor(bitmap, x + w, (y + h / 2), rect_color))
            return false;
        if (!IsOfColor(bitmap, (x + w / 2), y + h, rect_color))
            return false;

        return true;
    }
#endif

    // Checks whether there is a white canvas with a black square at the given
    // location in pixels (not in the canvas coordinate system).
    bool VerifyBlackRect(const SkCanvas& canvas, int x, int y, int w, int h)
    {
        return VerifyRect(canvas, SK_ColorWHITE, SK_ColorBLACK, x, y, w, h);
    }

#if !defined(USE_AURA) // http://crbug.com/154358
    // Check that every pixel in the canvas is a single color.
    bool VerifyCanvasColor(const SkCanvas& canvas, uint32_t canvas_color)
    {
        return VerifyRect(canvas, canvas_color, 0, 0, 0, 0, 0);
    }
#endif // !defined(USE_AURA)

#if defined(OS_WIN)
    void DrawNativeRect(SkCanvas& canvas, int x, int y, int w, int h)
    {
        skia::ScopedPlatformPaint scoped_platform_paint(&canvas);
        HDC dc = scoped_platform_paint.GetPlatformSurface();

        RECT inner_rc;
        inner_rc.left = x;
        inner_rc.top = y;
        inner_rc.right = x + w;
        inner_rc.bottom = y + h;
        FillRect(dc, &inner_rc, reinterpret_cast<HBRUSH>(GetStockObject(BLACK_BRUSH)));
    }
#elif defined(OS_MACOSX)
    void DrawNativeRect(SkCanvas& canvas, int x, int y, int w, int h)
    {
        skia::ScopedPlatformPaint scoped_platform_paint(&canvas);
        CGContextRef context = scoped_platform_paint.GetPlatformSurface();

        CGRect inner_rc = CGRectMake(x, y, w, h);
        // RGBA opaque black
        CGColorRef black = CGColorCreateGenericRGB(0.0, 0.0, 0.0, 1.0);
        CGContextSetFillColorWithColor(context, black);
        CGColorRelease(black);
        CGContextFillRect(context, inner_rc);
    }
#else
    void DrawNativeRect(SkCanvas& canvas, int x, int y, int w, int h)
    {
        NOTIMPLEMENTED();
    }
#endif

    // Clips the contents of the canvas to the given rectangle. This will be
    // intersected with any existing clip.
    void AddClip(SkCanvas& canvas, int x, int y, int w, int h)
    {
        SkRect rect;
        rect.set(SkIntToScalar(x), SkIntToScalar(y),
            SkIntToScalar(x + w), SkIntToScalar(y + h));
        canvas.clipRect(rect);
    }

    class LayerSaver {
    public:
        LayerSaver(SkCanvas& canvas, int x, int y, int w, int h)
            : canvas_(canvas)
            , x_(x)
            , y_(y)
            , w_(w)
            , h_(h)
        {
            SkRect bounds;
            bounds.set(SkIntToScalar(x_), SkIntToScalar(y_),
                SkIntToScalar(right()), SkIntToScalar(bottom()));
            canvas_.saveLayer(&bounds, NULL);
            canvas.clear(SkColorSetARGB(0, 0, 0, 0));
        }

        ~LayerSaver()
        {
            canvas_.restore();
        }

        int x() const { return x_; }
        int y() const { return y_; }
        int w() const { return w_; }
        int h() const { return h_; }

        // Returns the EXCLUSIVE far bounds of the layer.
        int right() const { return x_ + w_; }
        int bottom() const { return y_ + h_; }

    private:
        SkCanvas& canvas_;
        int x_, y_, w_, h_;
    };

    // Size used for making layers in many of the below tests.
    const int kLayerX = 2;
    const int kLayerY = 3;
    const int kLayerW = 9;
    const int kLayerH = 7;

    // Size used by some tests to draw a rectangle inside the layer.
    const int kInnerX = 4;
    const int kInnerY = 5;
    const int kInnerW = 2;
    const int kInnerH = 3;

}

// This just checks that our checking code is working properly, it just uses
// regular skia primitives.
TEST(PlatformCanvas, SkLayer)
{
    // Create the canvas initialized to opaque white.
    sk_sp<SkCanvas> canvas(CreatePlatformCanvas(16, 16, true));
    canvas->drawColor(SK_ColorWHITE);

    // Make a layer and fill it completely to make sure that the bounds are
    // correct.
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        canvas->drawColor(SK_ColorBLACK);
    }
    EXPECT_TRUE(VerifyBlackRect(*canvas, kLayerX, kLayerY, kLayerW, kLayerH));
}

#if !defined(USE_AURA) // http://crbug.com/154358
// Test native clipping.
TEST(PlatformCanvas, ClipRegion)
{
    // Initialize a white canvas
    sk_sp<SkCanvas> canvas(CreatePlatformCanvas(16, 16, true));
    canvas->drawColor(SK_ColorWHITE);
    EXPECT_TRUE(VerifyCanvasColor(*canvas, SK_ColorWHITE));

    // Test that initially the canvas has no clip region, by filling it
    // with a black rectangle.
    // Note: Don't use LayerSaver, since internally it sets a clip region.
    DrawNativeRect(*canvas, 0, 0, 16, 16);
    EXPECT_TRUE(VerifyCanvasColor(*canvas, SK_ColorBLACK));

    // Test that intersecting disjoint clip rectangles sets an empty clip region
    canvas->drawColor(SK_ColorWHITE);
    EXPECT_TRUE(VerifyCanvasColor(*canvas, SK_ColorWHITE));
    {
        LayerSaver layer(*canvas, 0, 0, 16, 16);
        AddClip(*canvas, 2, 3, 4, 5);
        AddClip(*canvas, 4, 9, 10, 10);
        DrawNativeRect(*canvas, 0, 0, 16, 16);
    }
    EXPECT_TRUE(VerifyCanvasColor(*canvas, SK_ColorWHITE));
}
#endif // !defined(USE_AURA)

// Test the layers get filled properly by native rendering.
TEST(PlatformCanvas, FillLayer)
{
    // Create the canvas initialized to opaque white.
    sk_sp<SkCanvas> canvas(CreatePlatformCanvas(16, 16, true));

    // Make a layer and fill it completely to make sure that the bounds are
    // correct.
    canvas->drawColor(SK_ColorWHITE);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), 0, 0, 100, 100);
#endif
    }
    EXPECT_TRUE(VerifyBlackRect(*canvas, kLayerX, kLayerY, kLayerW, kLayerH));

    // Make a layer and fill it partially to make sure the translation is correct.
    canvas->drawColor(SK_ColorWHITE);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        DrawNativeRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kInnerX, kInnerY, kInnerW, kInnerH);
#endif
    }
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH));

    // Add a clip on the layer and fill to make sure clip is correct.
    canvas->drawColor(SK_ColorWHITE);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        canvas->save();
        AddClip(*canvas, kInnerX, kInnerY, kInnerW, kInnerH);
        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kInnerX, kInnerY, kInnerW, kInnerH);
#endif
        canvas->restore();
    }
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH));

    // Add a clip and then make the layer to make sure the clip is correct.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    AddClip(*canvas, kInnerX, kInnerY, kInnerW, kInnerH);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), 0, 0, 100, 100);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH));
}

#if !defined(USE_AURA) // http://crbug.com/154358

// Test that translation + make layer works properly.
TEST(PlatformCanvas, TranslateLayer)
{
    // Create the canvas initialized to opaque white.
    sk_sp<SkCanvas> canvas(CreatePlatformCanvas(16, 16, true));

    // Make a layer and fill it completely to make sure that the bounds are
    // correct.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    canvas->translate(1, 1);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), 0, 0, 100, 100);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyBlackRect(*canvas, kLayerX + 1, kLayerY + 1,
        kLayerW, kLayerH));

    // Translate then make the layer.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    canvas->translate(1, 1);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        DrawNativeRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kInnerX, kInnerY, kInnerW, kInnerH);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX + 1, kInnerY + 1,
        kInnerW, kInnerH));

    // Make the layer then translate.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        canvas->translate(1, 1);
        DrawNativeRect(*canvas, kInnerX, kInnerY, kInnerW, kInnerH);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kInnerX, kInnerY, kInnerW, kInnerH);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX + 1, kInnerY + 1,
        kInnerW, kInnerH));

    // Translate both before and after, and have a clip.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    canvas->translate(1, 1);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        canvas->drawColor(SK_ColorWHITE);
        canvas->translate(1, 1);
        AddClip(*canvas, kInnerX + 1, kInnerY + 1, kInnerW - 1, kInnerH - 1);
        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kLayerX, kLayerY, kLayerW, kLayerH);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyBlackRect(*canvas, kInnerX + 3, kInnerY + 3,
        kInnerW - 1, kInnerH - 1));

// TODO(dglazkov): Figure out why this fails on Mac (antialiased clipping?),
// modify test and remove this guard.
#if !defined(OS_MACOSX)
    // Translate both before and after, and have a path clip.
    canvas->drawColor(SK_ColorWHITE);
    canvas->save();
    canvas->translate(1, 1);
    {
        LayerSaver layer(*canvas, kLayerX, kLayerY, kLayerW, kLayerH);
        canvas->drawColor(SK_ColorWHITE);
        canvas->translate(1, 1);

        SkPath path;
        SkRect rect;
        rect.iset(kInnerX - 1, kInnerY - 1,
            kInnerX + kInnerW, kInnerY + kInnerH);
        const SkScalar kRadius = 2.0;
        path.addRoundRect(rect, kRadius, kRadius);
        canvas->clipPath(path);

        DrawNativeRect(*canvas, 0, 0, 100, 100);
#if defined(OS_WIN)
        MakeOpaque(canvas.get(), kLayerX, kLayerY, kLayerW, kLayerH);
#endif
    }
    canvas->restore();
    EXPECT_TRUE(VerifyRoundedRect(*canvas, SK_ColorWHITE, SK_ColorBLACK,
        kInnerX + 1, kInnerY + 1, kInnerW, kInnerH));
#endif
}

#endif // #if !defined(USE_AURA)

} // namespace skia
